Caribsea Aquarium Substrate and Supply FAQ

Which grade do I use in a calcium reactor?
New A.R.M. Calcium Reactor Media is specifically designed for reactors. It concentrates Halimeda sp. , an aragonite so pure its used as a laboratory standard. A.R.M. has 50 times the strontium of other brands with only about 1/2 the phosphate and silica.

See "New Products" for more information.

Why is aragonite better than other calcium carbonates for calcium reactors?
Because it is more soluble, it takes less carbon dioxide to break it down, plus it has the great trace elements like strontium and magnesium.

Which is the best for plenums?
The Seaflor Special Grade Reef Sand, about 3-4" deep, or you can make a split layer plenum where the bottom 1-2 inches is Florida Crushed Coral and the upper layer Special Grade Reef Sand. You can also use Flamingo Reef or Bermuda Pink, which are the same products but with a little bit of pink calcium cabonate added for color.

Do I have to use a plenum?
The word is still out on this subject. Theoretically the plenum has an advantage over systems with aragonite directly on the bottom. However, if you don’t want to go through the effort of building a plenum, a deep bed of aragonite on the bottom of your tank will still do wonders for pH support, biological filtration, (including nitrate reduction) and calcium input.

What about "clumping"?
I heard that aragonite can get clumped up and hard in the tank. Why is that? Aragonite only gets bound together when the hobbyist is using large amounts of calcium and buffer additives, especially in conjunction with kalkwasser. Even so, it is very rare, and if it does happen, just settle down a bit on your additives. The fact is that the aragonite should be able, if there is a deep enough bed, to supply all your calcium and buffer needs on its own.

What if I don’t want a lot of sand on the bottom of my tank?
Then use a 1-1.5 inch layer of one of the oolitic sands (Aragamax) or Fiji Pink. You can still get denitrification, and some calcium and pH support. You may need to boost the levels now and then with a 2 part additive, or by using the Aragamight powder in your top off water. Also, if you have a sump, its a great place to put lots of aragonite without filling up your main tank. A deep bed of aragonite in a sump can give you the same results as 3 inches in your main tank. See "Systems" and look for "Passive".

Do you ever need to replace the aragonite in my tank?
No. Unlike other marine gravels, aragonite will not stop buffering over time. You may need to add a few pounds here and there over the years to top off but thats it.

Do I have to rinse aragonite?
A quick rinse is fine, any remaining cloudiness will disappear when the pumps and filters get going.

Where does aragonite come from?
From an island in the middle of the bahama banks. In fact, there is only one aragonite mine in the world, although most reef collected "live sands" will have some aragonite in them. CaribSea aragonite is pure, which makes it a great extender for live sand.

What will aragonite bring my calcium levels too? What about pH?
Aragonite drives towards seawater values. Calcium levels between 350-450, and a pH of 8.2.

What is Aragamight powder? Do I still need to use Kalkwasser?
Aragamight powder is ideal for remineralizing purified water. It will add a balanced portion of calcium, carbonate, and trace elements Hobbyists can also add it in heavier concentrations. You can’t overdose on aragonite because once the tank gets to seawater parameters, the aragonite stops going into solution. However, if your tank needs aragonite a few days later, the Aragamight powder is still in the tank and will then break down. Aragamight is different than Kalkwasser because it has a bettersource of calcium, but also carries in a buffer, plus trace elements with nothing else. As with the aragonite gravel, there is nothing in Aragamight that can’t be found in hard coral skeletons, and nothing in hard coral skeletons that can’t be found in Aragamight. On larger systems, however, Kalkwasser can help eliminate carbon dioxide build-up, and may be dosed in at night to prevent night time pH drops. The dosage however, can be reduced if Aragamight is used because the calcium will be taken care of. Aragamight also makes a great buffer for marine fish tanks and african cichlid tanks. Again, there is no worry of overdose, and it will not skyrocket your pH. It works as an "on-demand" buffer. Also, check out AragaMilk Liquid Aragonite in the "New Products" section.

Can you use aragonite is freshwater tanks?
Only brackish or African cichlid tanks. Aragonite can increase pH in freshwater to about 8.4-9.0, depending on the bio-load. You can even put some aragonite in an outside filter, or mix some in with your colored or river type gravels. You can also use our one of our African Cichlid Mix substrates which blend aragonite, calcite, and other minerals to maintain a high pH, but at the same time, provide a darker, more rift lake looking background for brighter colored fish and a more interesting aquascape.

How long does it take aragonite to cycle?
Usually in 4-6 weeks you have a pretty fully colonized bed of bacteria. We like to use Marc Weiss’s Bacter-Vital to speed things up and get a good broad spectrum of bacteria, or get thing started with a gallon or so of our new Araga-Live. See "New Products". You can also maintain a healthy bacteria count by using Coral Vital or Coral Vital LSB. These products help prevent algae growth naturally, by giving bacteria the advantage, not algaes.